1. Field of the Invention
The present invention relates to a plasma display device. More particularly, the invention relates to a power supply for supplying a voltage for driving the plasma display device.
2. Description of the Related Art
A plasma display device is a display device that uses plasma generated by gas discharge to display characters and/or images. A plasma display device may include millions of pixels arranged in a matrix pattern. The number of pixels in a plasma display device generally depends on the size of the plasma display device. Plasma display devices may be classified as a direct current (DC) type or an alternating current (AC) type based on the discharge cell structure and the waveform of the driving voltage applied to the plasma display device.
A DC-type plasma display device may have electrodes exposed to a discharge space. The electrodes enable direct current to flow through the discharge space when a voltage is applied. Therefore, such DC-type plasma display devices generally require a resistance for limiting the current.
An AC-type plasma display device may have electrodes covered with a dielectric layer that forms a capacitance component that helps limit the current and helps protect the electrodes from damage that may occur from the impact of ions colliding with boundaries of the discharge cells during discharge. Generally, AC-type plasma display devices may have longer lifetimes than DC-type plasma display devices.
Plasma display devices may sequentially display a plurality of frames displaying respective images that appear to be continuous to the human eye. For example, a plasma display device may display 30 to 60 frames per second. Each frame generally includes a plurality of sub-fields, e.g., 8 to 12 sub-fields per frame.
Each subfield may include a reset period, an addressing period, and a sustain period. During the reset period, the status of each discharge cell may be initialized. Initialization may facilitate an addressing operation that may be performed later on the discharge cell. During the addressing period, respective ones of the discharge cells of the plasma display device may be selectively turned on, i.e., addressed or turned-off. During the sustain period, a discharge may be initiated in the discharge cells turned on, i.e., addressed, during the previous addressing period to display an image.
To perform various operations, such as initializing, addressing and sustaining operations, the plasma display device may include a power supply for supplying power to the circuit(s)/component(s) of the plasma display panel. The power supply may supply the one or more voltages necessary for performing the various operations. For example, the power supply may supply one or more voltages, e.g., Vs, Vset, Ve, Va, Vnf, VscH and VscL, that may be required for performing a plasma discharge operation to a driving circuit of the plasma display device. The power supply may supply other circuits, such as an image processor, a fan, an audio amplifier, and a control circuit with a voltage for operating the respective circuits.
Generally, the cost of the power supply depends on the number and/or magnitude of the voltages, e.g., Vs, Ve, Va, etc., that the power supply is to supply. Know power supplies employ a separate power source for each of the various voltages. As each power source is associated with a cost, in general, the greater then number of power sources a power supply requires in order to supply the different voltages, the greater the cost of the power supply. Thus, in general, the greater the number of different voltages that the power supply is to generate, the greater the number of power sources and the cost of the power supply.
The information disclosed above in this Background section is only provided only to aid in the understanding of one or more aspects of the invention and is not to be considered nor construed as constituting prior art.